Camshaft controller, in particular for use in an induction manifold system for a multi-cylinder internal combustion engine

ABSTRACT

A camshaft controller (10), in particular for use in an induction manifold system for a multi-cylinder internal combustion engine, including an induction distributor (11) with individual induction pipes (16 to 19) which are disposed adjacent one another and terminate in a flange. The camshaft controller (10) is disposed in a longitudinal bore in the individual induction pipes (16 to 19) and serves to open and close the induction pipes. Associated with each individual induction pipe is a sealing element (43 to 50) which is secured to the camshaft controller (10).

BACKGROUND OF THE INVENTION

The invention relates to a camshaft controller, especially for use in aninduction manifold system for a multicylinder internal combustionengine.

A camshaft controller of this kind is disclosed, for example, in U.S.Pat. No. 4,932,369. It is disposed in an air induction system, aninduction manifold being provided from which individual intake tubesarranged side by side lead to a flange. This air induction system isfastened by this flange to the cylinder head of a multicylinder internalcombustion engine. The individual intake tubes are intersected by alongitudinal bore. In this longitudinal bore a camshaft controller isprovided, which is configured such that the length of the air intaketube is varied by turning it.

Furthermore, an induction tube apparatus for a multicylinder internalcombustion engine is disclosed in DE-OS 4344504. It too has a camshaftcontroller which is disposed in a longitudinal bore, and the camshaftcontroller can be used to connect or disconnect additional ducts.

If the induction system consists of plastic, it is necessary to equalizemanufacturing tolerances by appropriate elements, such as an impressedmetal sleeve. Manufacture thus becomes very expensive. Moreover there isthe problem that any recycling of the plastic component and theincorporated metal sleeve is impossible or possible only after acorresponding complicated disassembly.

SUMMARY OF THE INVENTION

It is the object of the invention to avoid the described disadvantagesand to provide a camshaft controller which is well sealed and in whichtolerances are effectively compensated.

This object is achieved by the invention as described and claimedhereinafter.

The substantial advantage of the invention is that the camshaftcontroller has sealing elements associated with the individual intaketubes, the sealing elements having a negligible effect on the torquerequired for driving the camshaft controller.

In an especially advantageous embodiment of the invention, the sealingelement is made up of two sealing bars which are parallel to one anotherand are joined at their ends by radially elastic ring elements. Thus asealed window is formed, which due to the elasticity of the ringelements is in resilient contact between the camshaft controller and theinner wall of the longitudinal bore and thus reliably seals eachindividual passage and each flow cross section of the individual intaketubes. The sealing element can be disposed at the entrance or exitopening of the induction tube. It is useful to provide it where itproduces the best effect.

An advantageous embodiment of the invention furthermore consists infixing the ring elements in grooves in the camshaft controller. The ringelements in that case are snapped like a clamp over the camshaftcontroller and seal the latter in the manner of a piston ring.

An additional embodiment of the camshaft controller provides for formingthe latter of individual segments. In that case the segments are joinedtogether such that, on the one hand, a great torsional stiffness isachieved, but on the other hand a certain radial mobility remains inorder to compensate tolerances.

It is furthermore advantageous to provide at least one end of thecamshaft controller with a bearing, the bearing bush being fastened in asocket of the induction system with a resilient element interposed. Theinterposition of the resilient element damps vibrations and also resultsin compensation of tolerances.

The rotation of the camshaft controller is advantageously effected by anactuator. This can be an electric motor, a vacuum box or any desiredhydraulically or mechanically driven element. The adjusting motion isadvantageously transferred by a radially movable claw clutch.

In addition, a clutching or connection between the actuator and thecamshaft controller can be performed by a pin and bushing, the latterbeing connected together with the interposition of a damping element,such as an O-ring for example. The use of the camshaft controller ispossible wherever a duct or a chamber must be switched open and closed.For example, its application to an adaptive bypass resonator isconceivable.

The application of sealing elements to the camshaft controller enablesthe longitudinal bore to have a conical shape. By means of this conicalconfiguration, it becomes simpler to remove the air induction systemfrom its mold.

These and additional features of preferred embodiments of the inventionwill be found not only in the claims but also in the description and thedrawings, and the individual features can be realized each by itself ortogether in the form of subcombinations in the embodiment of theinvention and in other fields, and can constitute advantageous as wellas independently patentable embodiments, for which protection is herebyclaimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained hereinafter with reference to workingembodiments.

FIG. 1 shows a longitudinal section of a camshaft controller in aninduction manifold system,

FIG. 2 shows a detail view of the camshaft controller,

FIG. 3 shows a perspective view of a sealing cage,

FIG. 4 shows a sectional view of the sealing cage,

FIG. 5 shows a detail of an induction manifold system with a rotaryvalve in the closed position,

FIG. 6 shows a detail of an induction manifold system with a rotaryvalve in the open position.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A plan view according to FIG. 1, with a camshaft controller in aninduction manifold system, shows an air intake manifold 11 for afour-cylinder internal combustion engine. From the air intake manifold11, individual induction tubes 12, 13, 14, 15, extend to a connectingflange, not shown here. A camshaft controller 10 opens or closesso-called power ducts. These can comprise shorter individual inductiontubes 16, 17, 18, 19, which likewise open through the connecting flange.The camshaft controller 10 has openings 20, 21, 22, 23. Between theseare supporting rods 24, 25, 26, 27. The camshaft controller is mountedthrough a bearing 28 and a resilient element in the intake manifoldhousing 29. At the opposite end the camshaft controller has a lever arm30 by which an actuator, not shown here, can rotate it to severalpositions.

The slide bearing 28 is mounted resiliently through an O-ring 66 in arecess 61 of the air intake manifold 11. In this way length tolerancescan be compensated. Also, the resilient mounting provides for thedamping of vibrations. The lever arm 30 is equipped with sections 62,63. These extend into grooves 64, 65, and thus form a claw clutch. Inaddition a resilient coupling is provided through an O-ring 66 betweenthe lever arm 30 and the camshaft controller 10. A spring 67 providesfor compensation of tolerances in length.

In FIG. 2 a camshaft controller 10 is shown in a detail view. Thiscamshaft controller has openings 31, 32, 33, 34, for the passage of theintake air. Grooves 35 to 42 are provided laterally at the openings. Asealing element in the form of a sealing cage 43-46 is inserted intoeach of these grooves.

FIG. 3 shows a perspective view of a sealing cage. This is comprised oftwo sealing bars 51, 52. These may extend parallel and are connected ateach of their ends with a respective ring 53, 54.

In the detailed illustration of FIG. 4, it can be seen that each of thesealing bars 51, 52, has a projection formed thereon. These projectionsare designed so that the sealing cage will enter and engage intoundercuts of the camshaft controller and at the same time provide asealing function. The ring 54 is open opposite the area where thesealing bars 51, 52, are fastened, and thus it can straddle the steppingcylinder and enter into the corresponding grooves. In the installedstate, the end portions 55, 56, of the ring 54 overlap each other bymeans of an inclined face formed on each of them, and thus form a closedsealing ring in the manner of a piston ring.

FIG. 6 shows the camshaft controller 10 in the closed position in anindividual induction tube 12 of an air intake manifold 11. In theupstream area, the sealing cage 43 seals off the entrance opening bymeans of the two sealing bars 51, 52. Also, the ring 53 provides forlateral sealing and thus simultaneously prevents any cross flow in thelongitudinal bore. To open the individual induction tube 12, thecamshaft controller 10 is rotated approximately 90°. On account of thespring-like properties of the rings of the sealing cage, it is assuredthat in every position of the camshaft controller the rings as well asthe two sealing bars will be in contact with the wall of thelongitudinal bore and thereby assure the sealing action.

FIG. 5 shows the variant of an air induction system with a rotary valvein the open position, i.e., in this case inducted air can additionallyflow according to the arrow 68 into the main air induction duct 69. Therotary valve or camshaft controller 10 is provided with transverseopenings 70, 71, 72, 73. These establish a connection between theindividual air intake ducts in the open position, and thus improve thedelivery of air to the individual cylinders of the internal combustionengine.

What is claimed is:
 1. A camshaft controller arrangement for an airinduction system for a multi-cylinder internal combustion enginecomprising an air intake manifold and individual air intake tubesarranged side by side and terminating in a flange, wherein said camshaftcontroller arrangement is disposed in a longitudinal bore in theindividual air intake tubes for closing and opening inlet or outletopenings of the individual air intake tubes, said camshaft controllerarrangement having a controller element and a sealing element disposedthereon and associated with each individual air intake tube, saidsealing element comprising at least two parallel sealing bars which areconnected at their ends by radially resilient ring elements, saidsealing bars being resiliently in contact with said longitudinal bore inwhich the controller element is disposed, at the inlet or outlet openingof each individual air intake tube, and said sealing bars havingprojections for engaging said controller element.
 2. A camshaftcontroller arrangement according to claim 1, wherein said resilient ringelements are fixed in grooves in the camshaft controller.
 3. A camshaftcontroller arrangement according to claim 1, wherein said controller iscomprised of individual segments which are coupled to one another in atorsionally rigid and radially movable manner.
 4. A camshaft controllerarrangement according to claim 1, wherein at least one end of saidcamshaft controller element is journaled in a bearing bush secured in arecess in the air induction system by a resilient element interposedbetween said bearing bush and said recess.
 5. A camshaft controllerarrangement according to claim 1, further comprising an actuator forturning the camshaft controller and a claw clutch for connecting theactuator to the camshaft controller element so that movement of theactuator is transmitted to the camshaft controller element.
 6. Acamshaft controller arrangement according to claim 1, wherein a pivotbearing is provided, which has a resilient element between the pivot andthe bush.
 7. A camshaft controller arrangement according to claim 1,wherein said resilient element is an O-ring.
 8. A camshaft controllerarrangement according to claim 1, wherein said controller is providedwith transverse openings which form cross connections between theindividual intake tubes when the individual intake tubes are open.